X99X Fataility - 950 Pro Not Listed in Storage

I just set up my new system, and while the motherboard is clearly recognizing the drive and i was able to install windows 10 and boot to it, it is not visible under the Advanced\Storage Configuration area of the bios. I can set it as the boot device in the Boot tab, but looking at the list of drives shows in the Advanced tab nothing in the m2 slot. So, there isn't explicitly any problem, but I am very curious about what this page of the interface is supposed to do if it doesn't even see the drive while some other part of the board does. Common sense says the drive should be there, and the lack of it being there doesn't sit right.

Edited by Omnitographer - 05 Nov 2015 at 3:53am

fdisker wrote: Same here in my Z97 Pro4.  I have the 950 in a PCIe adapter and I don't see it listed in the BIOS.  No problems installing Windows 10.  I'm curious about it too.  I pulled my 850 EVO out of the M.2 slot before installing the 950 and now I'm wondering what will happen if I put the 850 back in the slot.  Will I be able to choose my boot device?  Will the 950 continue to boot? Won't be able to test until I get home tonight but I'll let you know.

What you both are experiencing is typical and normal behavior when using PCIe SSDs, particularly NVMe PCIe SSDs.

I've seen the same thing when I had two AHCI SM951 PCIe SSDs in RAID 0 on my ASRock Z170 Extreme7+ board. The two SM951s were not listed in the Storage Configuration screen once they were in the RAID array. They also were not detected by the System Browser tool.

The only places the RAID 0 array was shown was in the Intel IRST utility that appears in the Advanced screen of the UEFI, when CSM is disabled, or the Launch Storage OpROM policy is set to UEFI Only. It was also shown in the Boot drive list. In Windows it is detected by Windows Explorer, and the IRST Windows utility.

Don't forget that you are now using storage devices that are using multiple, different protocols. SATA and AHCI are different than NVMe, and use different drivers. This situation is similar to old mother boards that supported both SATA drives and IDE HDDs, that used ribbon cables and 40 pin connectors. The two interfaces were separated and the BIOS had settings to enable and configure the IDE HDDs.

We are familiar with using only one common interface for our storage drives, SATA. That's all we've had for almost ten years. That made things convenient and simple. Now we have a new interface, PCIe via M.2 ports or PCIe slots. Add to that a new protocol, NVMe, and things become complicated and different.

M.2 ports can support multiple interfaces, PCIe and SATA. SATA type M.2 SSDs and PCIe M.2 SSDs have different "keys" on the part that connects to the M.2 port/slot. The difference in the keys is what tells the board which type of drive is being used, and activates the appropriate interface for the drive.

AHCI PCIe SSDs (Samsung XP941, AHCI SM951 version) have the equivalent of a mother board's storage controller built into the drive. They don't use the (SATA) storage controller in the board's chipset, and are not included/detected by the Intel IRST software.

One new exception to this is available on Z170 chipset boards with the latest Intel IRST driver. When RAID mode is used and more than one AHCI PCIe SSD is installed in the board, the IRST software will include those SSDs with SATA drives in its listing of drives, and allow them (PCIe SSDs) to be combined into a RAID 0 array.

Frankly given all this complexity, IMO it is amazing the PCIe SSDs work as well as they do. The PCIe SSD, mother board, OS and UEFI firmware manufactures have done a great job of getting these drives to work on a platform that has been (and still is) SATA based for a long time. The non-standard behavior of PCIe SSDs in the UEFI is surprising and confusing, particularly when no explanation about what to expect is provided by any of the parties involved.

I imagine this will be sorted out eventually. Currently PCIe SSDs are new cutting edge products that are truly different. We are simply living with the pain of being early adopters.

fdisker, I assume your 850 EVO has an OS installed on it?

Why wouldn't the 850 be able to be seen as a boot device? The 850 EVO is a SATA type M.2 SSD. I've had multiple OS drives used on ASRock Z97 and Z170 boards, one PCIe SSD or two PCIe SSDs in RAID 0, and one SATA SSD. Both appear in the Boot order list and can be selected and booted from fine.

Edited by cblx5 - 14 Dec 2015 at 7:49pm